1. Field of the Invention
The present invention relates to a sound pickup apparatus and an echo cancellation processing method preferable for use when, for example, a plurality of conference participants in two distant conference rooms hold an audio teleconference by using a plurality of microphones, and, preferably, hold a voice+television conference by adding a video.
In particular, the present invention relates to a sound pickup apparatus and an echo cancellation processing method that an echo cancellation use calibration sound is applied before use of the sound pickup apparatus, an echo cancellation use parameter is learned and generated by an echo canceller because the echo canceller does not have an adequate echo cancellation use parameter in an initial state.
2. Description of the Related Art
A TV conference system having a sound pickup apparatus or a sound pickup apparatus that a picture image is added has been used to enable conference participants in two conference rooms at distant location to hold a conference.
In a sound pickup apparatus, a microphone is selected, where the microphone is used by a speaking person whose voice should be transmitted to a conference room of the other party among the speaking persons using a plurality of microphones.
An echo canceller is placed in such a sound pickup apparatus, and the echo canceller prevents becoming hard to hear due to transmit of an echo of a sending side to a sound receiving side.
The echo canceller performs the echo cancellation processing with performing learning processing for a sound from the selected microphone among a plurality of microphones with using an echo cancellation use parameter (learning data). Therefore, in the echo canceller, an echo cancellation use parameter of each microphone is held.